First of all download the zip file of the Hello Shoppable Pro Theme. After that follow the theme installation process from How to Install Theme.
After installing Hello Shoppable pro theme click on activate theme then you will be directed to license key page.
You can use provided license key.
Click on activate license and after successful activation you will be terminate next page
Click on the Getting Started button to install the necessary plugins (you can delete them after). Wait for the plugins to install and there you go you are ready to use Hello Shoppable pro.